The biology and treatment of plasmablastic lymphoma. Blood. 2015;125:2323-2330. [PMID: 25636338 DOI: 10.1182/blood-2014-10-567479]

Intraocular Plasmablastic Lymphoma in a HIV Patient

Plasmablastic lymphoma (PBL) is a rare B-cell lymphoma occurring mainly in HIV patients. The tumor frequently involves extranodal sites such as the oral cavity, nasal cavity, gastrointestinal tract, skin, and lungs. The neoplastic cells are characterized by a plasmablastic appearance and typical immunophenotype that indicates plasma cell differentiation. Herein, we report a case of intraocular involvement by plasmablastic lymphoma in a HIV patient with a long history of cytomegalovirus retinitis and loss of vision. After an evisceration performed to control the blind, painful eye a diagnosis of PBL was made by examining the eye contents. Two months later, a biopsy of cervical lymph node revealed nodal lymphoma of the same type. To the best of our knowledge, this is the second case of intraocular PBL reported in English literature.

Interleukin-6-dependent growth in a newly established plasmablastic lymphoma cell line and its therapeutic targets

Plasmablastic lymphoma (PBL) is a rare, highly aggressive subtype of non-Hodgkin lymphoma with plasma-cell differentiation occurring typically in immune-suppressed patients such as those with AIDS. This study reports the establishment and characterization of a new cell line, PBL-1, derived from a patient with AIDS-associated PBL. Morphological assessment of PBL-1 indicated plasma-cell differentiation with a CD20(-) CD38(+) CD138(+) immunophenotype and IgH/c-myc translocation. The cell line harbours Epstein-Barr virus, but a 52.7-kbp length defect was identified in its genome, resulting in no expression of viral microRNAs encoded in the BamHI-A Rightward Transcript region. Importantly, supplementation of culture medium with >5 ng/mL of interleukin-6 (IL-6) was required for PBL-1 growth. Starvation of IL-6 or addition of tocilizumab, an inhibitory antibody for the IL-6 receptor, induced apoptosis of PBL-1. Transduction of IL-6 into PBL-1 by lentivirus vector induced autologous growth without IL-6 supplementation of culture medium. These data indicate the IL-6 dependency of PBL-1 for proliferation and survival. mTOR inhibitors induced cell death effectively, suggesting mTOR in the IL-6 signalling pathway is a potential therapeutic target for PBL. This established PBL cell line will be a useful tool to further understand the pathophysiology of PBL and aid the future development of PBL treatment.

Epstein-Barr virus associated lymphomas in people with HIV

PURPOSE OF REVIEW

The present review summarizes the association of the different histotypes of Epstein-Barr virus (EBV)-associated lymphomas with known genetic lesions and/or oncogenic viruses. A more comprehensive understanding of the complex interplay existing between genetic abnormalities of tumor cells and the viral contribution to the development of EBV-associated lymphomas is pivotal for the development of more effective treatments.

RECENT FINDINGS

Recent evidence indicates that HIV may contribute to lymphomagenesis by acting directly on B lymphocytes as a critical microenvironmental factor. The pathogenesis of EBV-associated lymphomas in patients with HIV infection is considered the result of the concerted action of different factors, mainly including impaired immune surveillance, genetic alterations, and concomitant viral infection (EBV and HIV).

SUMMARY

Immunodeficiency states usually increase susceptibility to cancer as a result of reduced immune surveillance and enhanced chances for virus-driven oncogenesis. Lymphoma remains the most frequent neoplastic cause of death among patients infected with HIV. Several of the HIV-associated lymphomas are related to EBV infection. EBV-associated lymphomas in patients infected with HIV are heterogeneous, not only pathologically but also in terms of pathogenetic pathways and cellular derivation.

A rare case of Epstein-Barr virus-related plasmacytoma involving maxillary sinus mucosa

Extramedullary plasmacytomas, Epstein–Bar virus (EBV) associated, are rarely encountered and usually have a fairly good clinical outcome. EBV+ plasmacytoma may cause a diagnostic dilemma as it phenotypically resembles an aggressive plasmablastic lymphoma (PBL). Herein, we report a unique case with maxillary EBV+ plasmacytoma from a 76‐year‐old immunocompetent individual.

Clinical characteristics and prognostic factors of plasmablastic lymphoma patients: analysis of 135 patients from the LYSA group

Background

Plasmablastic lymphoma (PBL), initially described in 1997 in the oral cavity of HIV positive patients, is now recognized as a distinct aggressive and rare entity of diffuse large B-cells lymphoma by the World Health Organization (WHO) classification. Since the original description, others cases have been reported. However, these are largely derived from case reports or small series limiting any definitive conclusions on clinical characteristics and outcome.

Patients and methods

The clinical, biological, pathological features and outcome of a cohort including 135 patients with PBL, from LYSA centers in France and Belgium, were reported and analyzed.

Results

The median age was 58 years, with a male predominance. The cohort was divided into 56 HIV-positive patients, 17 post-transplant patients and 62 HIV-negative/non-transplanted patients. Within HIV-negative/non-transplanted, a relative immunosuppression was found in most cases (systemic inflammatory disease, history of cancer, increased age associated with weakened immune system). We have also described a new subtype, PBL arising in a chronic localized inflammatory site, without any sign of immunosuppression. At presentation, 19% of patients showed oral involvement. Immunophenotype showed CD138 positivity in 88% of cases and CD20 negativity in 90% of cases. Chemotherapy was administered to 80% of patients, with a complete response (CR) rate of 55%. The median overall survival (OS) was 32 months. In univariate analysis, HIV positive status showed better OS when compared with HIV negative status. In multivariate analysis, International Prognostic Index score, chemotherapy and CR were associated with survival benefit.

Conclusion(s)

This cohort, the largest reported to date, increases the spectrum of knowledge on PBL, rarely described. However, specific guidelines to clarify treatment are lacking, and may improve the poor prognosis of this rare disease.

A case of HIV-negative plasmablastic lymphoma of the bone marrow with a unique immunophenotype

We present an interesting case of plasmablastic lymphoma, which is a rare type of non-Hodgkin lymphoma that is typically diagnosed in HIV-positive patients and has an immunophenotype that overlaps with multiple myeloma. Our patient is unique because he is HIV-negative, has primary bone marrow disease, and has an atypical immunophenotype.

Human immunodeficiency virus (HIV) and Epstein-Barr virus (EBV) related lymphomas, pathology view point

The contribution of Epstein Barr virus (EBV) and Kaposi sarcoma herpes virus (KSHV) to the development of specific types of malignant lymphomas occurring in the human immunodeficiency virus (HIV) setting has been extensively studied since the beginning of the HIV epidemic 35 years ago. The introduction of highly active antiretroviral therapies (HAART) in 1996 has changed dramatically the incidence of HIV-related malignancies. Nevertheless, malignant lymphomas continue to be the major group of malignances observed in HIV infected individuals, and the most common cause of cancer related-deaths. Common features of the predominant B-cell lymphomas in the HIV⁺ setting are the frequent plasmacytoid morphology of the neoplastic cells, advanced stage, aggressive disease and frequent extranodal involvement. In this article, we review the evolving concepts and definitions of the various EBV-associated lymphomas in HIV⁺ patients, including diffuse large B-cell lymphoma, Burkitt lymphoma, classical Hodgkin lymphoma, plasmablastic lymphoma and primary effusion lymphoma. The current knowledge regarding the pathogenesis of these malignancies, the interplay between HIV and EBV co-infection in the development of certain HIV related lymphomas, and the emerging paradigm that suggests that HIV may play a direct role in lymphomagenesis are explored as well.

Mouse model of Epstein-Barr virus LMP1- and LMP2A-driven germinal center B-cell lymphoproliferative disease

Epstein-Barr virus (EBV) is a major cause of immunosuppression-related B-cell lymphomas and Hodgkin lymphoma (HL). In these malignancies, EBV latent membrane protein 1 (LMP1) and LMP2A provide infected B cells with surrogate CD40 and B-cell receptor growth and survival signals. To gain insights into their synergistic in vivo roles in germinal center (GC) B cells, from which most EBV-driven lymphomas arise, we generated a mouse model with conditional GC B-cell LMP1 and LMP2A coexpression. LMP1 and LMP2A had limited effects in immunocompetent mice. However, upon T- and NK-cell depletion, LMP1/2A caused massive plasmablast outgrowth, organ damage, and death. RNA-sequencing analyses identified EBV oncoprotein effects on GC B-cell target genes, including up-regulation of multiple proinflammatory chemokines and master regulators of plasma cell differentiation. LMP1/2A coexpression also up-regulated key HL markers, including CD30 and mixed hematopoietic lineage markers. Collectively, our results highlight synergistic EBV membrane oncoprotein effects on GC B cells and provide a model for studies of their roles in immunosuppression-related lymphoproliferative diseases.

Chronic lymphocytic leukaemia with concomitant plasmablastic lymphoma

Plasmablastic lymphomas are high-grade lymphomas that usually occur in immune-suppressed patients. Occasionally, they can arise from an underlying haematolymphoid malignancy, termed ‘transformed plasmablastic lymphoma’. In this report, we describe a case of chronic lymphocytic leukaemia and plasmablastic lymphoma in an elderly HIV-negative patient.

Plasmablastic lymphoma versus plasmablastic myeloma: an ongoing diagnostic dilemma

Aims

To determine the utility of clinical, morphological and phenotypical features in the differential diagnosis of plasmablastic lymphoma and myeloma with plasmablastic features.

Methods

All plasmablastic neoplasms identified from a 15-year retrospective search were reviewed and classified into ‘lymphoma’, ‘myeloma’ or ‘indeterminate’. The classification was then compared with the previously established clinical diagnosis. Lessons learned from this review were used to design a diagnostic algorithm for pathologists to use in the absence of known clinical history.

Results

The classification was possible in 10 of 11 cases, 8 lymphomas and 2 myelomas (n=2). No distinctive morphological or phenotypical features were identified. The most useful histopathological parameter was a positive Epstein-Barr virus in situ hybridisation. Presence of associated lymphadenopathy and/or oral mass in the absence of complete myeloma-defining signs was used to favour a diagnosis of lymphoma in 4 of 8 cases.

Conclusions

The distinction between plasmablastic lymphoma from plasmablastic myeloma warrants detailed knowledge of clinical, radiological and laboratorial findings. New studies identifying distinctive phenotypical or genetic features are needed to improve the histopathological differentiation of plasmablastic neoplasms.

Plasmablastic lymphoma: Review of 60 Chinese cases and prognosis analysis

BACKGROUND

Plasmablastic lymphoma (PBL) is a B-cell malignancy associated with human immunodeficiency virus (HIV). PBL could also influence the HIV-negative patients. The study aimed to identify prognostic factors for survival among Chinese PBL patients.

MATERIALS AND METHODS

Eligible patients from literature and Peking Union Medical College Hospital (PUMCH) were included in this study. Clinical characteristics and immunophenotypic data were extracted. Kaplan-Meier curve was used to describe the survival status. Cox regression was used for multivariate analysis.

RESULTS

A total of 60 Chinese PBL patients were included, including 54 patients from 36 published articles and 6 new patients that have not been reported. The median overall survival was 7 months (95% confidence interval 3.853-10.147 months). An overwhelming majority (79.31%) of the included cases were Ann Arbor stage IV patients. All the Chinese PBL patients were HIV-negative; 46.81% were Epstein-Barr virus-positive. CD38, CD138, or MUM1 was positively expressed in more than 80% of patients; CD20 expression was also found in 22.03% of cases. Kaplan-Meier curve revealed obvious differences in patient survival between patients in primary stages and advanced stages, as well as between patients with kidney involvement and those without kidney involvement. Cox regression analysis indicated that stage and age were 2 prognostic factors for patient survival.

CONCLUSIONS

Advanced stage might be associated with poor prognosis among PBL HIV-negative patients in Chinese.

Vitamin D Receptor Expression in Plasmablastic Lymphoma and Myeloma Cells Confers Susceptibility to Vitamin D

Plasmablastic B-cell malignancies include plasmablastic lymphoma and subsets of multiple myeloma and diffuse large B-cell lymphomaDLBCL. These diseases can be difficult to diagnose and treat, and they lack well-characterized cell line models. Here, immunophenotyping and FOXP1 expression profiling identified plasmablastic characteristics in DLBCL cell lines HLY-1 and SU-DHL-9, associated with CTNNAL1, HPGD, RORA, IGF1, and/or vitamin D receptor (VDR) transcription. We demonstrated VDR protein expression in primary plasmablastic tumor cells and confirmed in cell lines expression of both VDR and the metabolic enzyme CYP27B1, which catalyzes active vitamin D3 production. Although Vdr and Cyp27b1 transcription in normal B cells were activated by interleukin 4 (IL-4) and CD40 signaling, respectively, unstimulated malignant plasmablastic cells lacking IL-4 expressed both VDR and CYP27B1. Positive autoregulation evidenced intact VDR function in all plasmablastic lines, and inhibition of growth by active vitamin D3 was both dependent on MYC protein inhibition and could be enhanced by cotreatment with a synthetic ROR ligand SR-1078. Furthermore, a VDR polymorphism, FOK1, was associated with greater vitamin D3-dependent growth inhibition. In summary, HLY-1 provides an important model of strongly plasmablastic lymphoma, and disruption of VDR pathway activity may be of therapeutic benefit in both plasmablastic lymphoma and myeloma.

Update from the 4th Edition of the World Health Organization Classification of Head and Neck Tumours: Hematolymphoid Tumours

In 2017, the latest revision to the WHO Classification of Head and Neck Tumours will be released. Similar to the 2005 WHO, the codification of hematopoietic and lymphoid neoplasms of the head and neck is included within chapters pertaining to the nasal cavity and paranasal sinuses, the nasopharynx, the larynx, the oral cavity and oropharynx, the neck and the salivary glands. Herein, we describe both changes to the classification of hematolymphoid neoplasms of the head and neck since the 2005 WHO, as well as recent advances in our understanding of the underlying pathogenesis and molecular pathology of these neoplasms.

Update from the 4th Edition of the World Health Organization of Head and Neck Tumours: Tumours of the Oral Cavity and Mobile Tongue

There have been several additions and deletions in Chapter 4 on Tumours of the oral cavity and mobile tongue in the 2017 fourth edition of the World Health Organization Classification of Tumours of the Head and Neck. This chapter excludes the oropharynx, which now is a stand-alone chapter acknowledging the uniqueness of the oropharynx from the oral cavity. New entries in Chapter 4 include rhabdomyoma, haemangioma, schwannoma, neurofibroma and myofibroblastic sarcoma in the section titled Soft tissue and neural tumours. Discussion of salivary gland entities have been reduced and includes mucoepidermoid carcinoma and pleomorphic adenoma as the other salivary gland types are discussed elsewhere. In the Haematolymphoid tumours section, like the salivary gland section, only tumors that commonly present in the oral cavity are discussed in Chapter 4. Excluded entities in the updated classification include papillary hyperplasia, median rhomboid glossitis, keratoacanthoma, focal oral mucinosis, and secondary tumors. This article will summarize the changes in the new classification since the 2005 edition focusing on selected entities that have had significant changes along with new entries.

HHV8/KSHV-Positive Lymphoproliferative Disorders and the Spectrum of Plasmablastic and Plasma Cell Neoplasms: 2015 SH/EAHP Workshop Report-Part 3

OBJECTIVES

The 2015 Workshop of the Society for Hematopathology/European Association for Haematopathology aimed to review immunodeficiency-related lymphoproliferative disorders with plasmablastic and plasma cell differentiation.

METHODS

The workshop panel reviewed human herpes virus 8 (HHV8)/Kaposi sarcoma herpesvirus (KSHV)-associated lesions and other lesions exhibiting plasma cell differentiation, including plasmablastic proliferations with features of myeloma/plasmacytoma, plasmablastic neoplasms presenting in extranodal sites and effusion-based lymphomas, and rendered a consensus diagnosis.

RESULTS

The spectrum of HHV8/KSHV-associated proliferations ranged from multicentric Castleman disease (MCD) to MCD with plasmablastic aggregates to HHV8+ diffuse large B-cell lymphoma and germinotrophic lymphoproliferative disorder. Comparisons across effusion-based lymphomas with and without HHV8/KSHV and plasmablastic lymphomas in immunodeficient and immunocompetent patients were discussed.

CONCLUSIONS

The presence or absence of HHV8/KSHV is a defining feature in disorders associated with Castleman disease, although their differential diagnosis and recognition of progression may be challenging. Plasmablastic proliferations overlap with myeloma/plasmacytoma as well as extranodal and effusion-based lymphomas. The involvement of Epstein-Barr virus is typically variable.

A Case of Plasmablastic Lymphoma Achieving Complete Response and Durable Remission after Lenalidomide-Based Therapy

BACKGROUND

Plasmablastic lymphoma (PBL) is an uncommon variant of diffuse large B-cell lymphoma that is characterized by its plasmacytoid features, aggressive tendencies, and frequent association with human immunodeficiency virus (HIV) infection or other immunocompromised states. Multi-agent, intensive chemotherapy regimens are recommended as first-line treatment by the National Comprehensive Cancer Network. However, the toxicity of these regimens is high and prognosis remains poor.

CASE REPORT

We report a patient with HIV-negative PBL who achieved complete response and durable remission using a lenalidomide-based chemotherapy regimen as first-line therapy.

CONCLUSION

Cyclophosphamide, lenalidomide, dexamethasone (CRD) may provide an alternative initial therapeutic option for patients with PBL who cannot tolerate the intensive chemotherapy regimens currently recommended.

Plasmablastic lymphoma phenotype is determined by genetic alterations in MYC and PRDM1

Plasmablastic lymphoma is an uncommon aggressive non-Hodgkin B-cell lymphoma type defined as a high-grade large B-cell neoplasm with plasma cell phenotype. Genetic alterations in MYC have been found in a proportion (~60%) of plasmablastic lymphoma cases and lead to MYC-protein overexpression. Here, we performed a genetic and expression profile of 36 plasmablastic lymphoma cases and demonstrate that MYC overexpression is not restricted to MYC-translocated (46%) or MYC-amplified cases (11%). Furthermore, we demonstrate that recurrent somatic mutations in PRDM1 are found in 50% of plasmablastic lymphoma cases (8 of 16 cases evaluated). These mutations target critical functional domains (PR motif, proline rich domain, acidic region, and DNA-binding Zn-finger domain) involved in the regulation of different targets such as MYC. Furthermore, these mutations are found frequently in association with MYC translocations (5 out of 9, 56% of cases with MYC translocations were PRDM1-mutated), but not restricted to those cases, and lead to expression of an impaired PRDM1/Blimp1α protein. Our data suggest that PRDM1 mutations in plasmablastic lymphoma do not impair terminal B-cell differentiation, but contribute to the oncogenicity of MYC, usually disregulated by MYC translocation or MYC amplification. In conclusion, aberrant coexpression of MYC and PRDM1/Blimp1α owing to genetic changes is responsible for the phenotype of plasmablastic lymphoma cases.

Refractory plasmablastic lymphoma-a review of treatment options beyond standard therapy

Plasmablastic lymphoma (PBL) is a rare distinct subtype of aggressive diffuse large B-cell lymphoma and a notoriously hard to treat entity with a dismal prognosis in both HIV-negative and HIV-positive patients. Clinicians often face the question of second or third line treatment. As the treatment options with novel agents in lymphomas are rapidly evolving, more and more options beyond standard chemotherapy are available. In connection with a review of treatment options with novel lymphoma agents, we present a case report of a patient with a complete remission after the administration of brentuximab vedotin and lenalidomide.

B-cell Lymphoproliferative Disorders Associated with Primary and Acquired Immunodeficiency

The diagnosis of lymphoproliferative disorders associated with immunodeficiency can be challenging because many of these conditions have overlapping clinical and pathologic features and share similarities with their counterparts in the immunocompetent setting. There are subtle but important differences between these conditions that are important to recognize for prognostic and therapeutic purposes. This article provides a clinicopathologic update on how understanding of these B-cell lymphoproliferations in immunodeficiency has evolved over the past decade.

B-cell Non-Hodgkin Lymphomas with Plasmacytic Differentiation

B-cell non-Hodgkin lymphomas with plasmacytic differentiation are a diverse group of entities with extremely variable morphologic features. Diagnostic challenges can arise in differentiating lymphoplasmacytic lymphoma from marginal zone lymphoma and other low-grade B-cell lymphomas. In addition, plasmablastic lymphomas can be difficult to distinguish from diffuse large B-cell lymphoma or other high-grade lymphomas. Judicious use of immunohistochemical studies and molecular testing can assist in appropriate classification.

Plasmablastic lymphoma mimicking carcinomatosis: A case report and review of the literature

First identified as a distinct disease entity in HIV-positive patients, plasmablastic lymphoma is a rare aggressive disease which arises predominantly in men and is associated with immunodeficiency of all causes. Although its exact etiology is poorly understood, Epstein-Barr virus infection and MYC gene aberrations have been implicated in its development in both HIV-positive and HIV-negative patients. The disease typically involves extranodal sites with a predilection for the oral cavity but may occur in other locations. Here we present a case of plasmablastic lymphoma diffusely involving the omentum and peritoneal cavity of an immunocompetent woman, clinically mimicking an ovarian carcinomatosis. To the best of our knowledge, this is the first case in which plasmablastic lymphoma has presented as peritoneal lymphomatosis. Diagn. Cytopathol. 2017;45:243-246. © 2016 Wiley Periodicals, Inc.

Bortezomib, Ifosfamide, Carboplatin, and Etoposide in a Patient with HIV-Negative Relapsed Plasmablastic Lymphoma

Plasmablastic lymphoma (PBL) is a rare subtype of diffuse large B cell lymphoma (DLBCL), often associated with HIV infection. We present a case of a 53-year-old HIV-negative man with untreated hepatitis C viral infection who presented with abdominal pain and lymphadenopathy. Lymph node and bone marrow biopsies were consistent with plasmablastic lymphoma. He had partial response (PR) to 6 cycles of EPOCH but disease progressed seven weeks later. Repeat biopsy was consistent with plasmablastic lymphoma. Three cycles of bortezomib, ifosfamide, carboplatin, and etoposide (B-ICE) chemotherapy resulted in a partial response (PR). Five months later, he presented with widespread lymphadenopathy and tumor lysis syndrome with circulating blasts. Flow cytometry revealed a different population of lymphoma cells, this time positive for CD5, CD19, CD20, and CD22, with dim expression of CD45 and CD38. The patient died on the first day of ESHAP chemotherapy. There are no treatment recommendations or standard of care for plasmablastic lymphoma. A literature search yielded 10 cases in which bortezomib was administered in either HIV-positive or HIV-negative PBL. Six reported a partial response, 3 reported a complete response, and 1 was a near-complete response. Bortezomib, in combination with chemotherapy, may be an effective treatment option in PBL as reported here.

What is that? HIV-negative plasmablastic lymphoma with intramuscular masses

Plasmablastic lymphoma is a relatively new clinical entity described as a distinct subtype of diffuse large B-cell lymphoma, although in the last decade several case reports and series have been published. This case is presented because of its rarity, as this pathology is rare in immunocompetent patients and intramuscular masses are present. We report the case of a 63-year-old male with no significant clinical background. He was referred to the emergency department of our hospital with a 10-day history of pain on the left side of the chest that was described as burning and spreading to the right side. On physical examination, he had no fever or recent weight loss. The abdomen was soft and non-distended, and no peritoneal signs were present but he had three palpable masses located in the soft tissues of the breast, right gluteal region and left leg. Histological examination of the biopsy specimens disclosed the diagnosis of plasmablastic lymphoma. To our knowledge, this will be the second case report referring to intramuscular masses in the English language literature.

Interim PET Scans in Diffuse Large B-Cell Lymphoma: Is It Ready for Prime Time?

Prognostication of patients with diffuse large B-cell lymphoma (DLBCL) has improved in the past decade with a variety of clinical, morphologic, molecular, and radiographic methods. Comparable to data on the value of interim positron emission tomography (I-PET) in Hodgkin lymphoma, several retrospective and prospective studies are attempting to assess the value of I-PET scanning in DLBCL patients. In this review, we briefly describe and analyze the various prognostic methods in DLBCL with specific focus on the value of I-PET scanning in this disease. This is a timely analysis, as tailoring therapies based on prognosis at diagnosis are becoming of increased investigational interest.

Plasmablastic Lymphoma: A Review of Clinicopathologic Features and Differential Diagnosis

Plasmablastic lymphoma (PBL) is a challenging diagnosis given its rarity and lack of expression of markers that are usually used by pathologists in establishing hematopoietic lineage. However, knowledge of the characteristic clinical setting, sites of involvement, and morphologic features of plasmablastic lymphoma can aid in the correct diagnosis of a suspected large cell lymphoma that is negative for B-cell– and T-cell–specific antigens. Herein, we review the clinical and pathologic features of plasmablastic lymphoma with an emphasis on the differential diagnosis of hematolymphoid neoplasms with immunoblastic morphology and/or evidence of plasmacytic differentiation by immunophenotype.

Recent insights in the pathogenesis of post-transplantation lymphoproliferative disorders

Post-transplant lymphoproliferative disorder (PTLD) is an aggressive complication of solid organ and hematopoietic stem cell transplantation that arises in up to 20% of transplant recipients. Infection or reactivation of the Epstein-Barr virus (EBV), a ubiquitous human herpesvirus, in combination with chronic immunosuppression are considered as the main predisposing factors, however insight in PTLD biology is fragmentary. The study of PTLD is complicated by its morphological heterogeneity and the lack of prospective trials, which also impede treatment optimization. Furthermore, the broad spectrum of underlying disorders and the graft type represent important confounding factors. PTLD encompasses different malignant subtypes that resemble histologically similar lymphomas in the general population. Post-transplant diffuse large B-cell lymphoma (PT-DLBCL), Burkitt lymphoma (PT-BL) and plasmablastic lymphoma (PT-PBL) occur most frequently. However, in many studies various EBV⁺ and EBV^- PTLD subtypes are pooled, complicating the interpretation of the results. In this review, studies of the gene expression pattern, the microenvironment and the genetic profile of PT-DLBCL, PT-BL and PT-PBL are summarized to better understand the mechanisms underlying post-transplantation lymphomagenesis. Based on the available findings we propose stratification of PTLD according to the histological subtype and the EBV status to facilitate the interpretation of future studies and the establishment of clinical trials.

[Clinical features and outcomes: analysis of 9 cases of HIV-negtive plasmablastic lymphoma]

Objective: To evaluate the clinical features and outcomes of HIV-negtive plasmablastic lymphoma (PBL). Methods: Nine patients with HIV-negtive PBL were diagnosed and treated between January 2006 and January 2016. The clinical and follow-up data were analyzed retrospectively. Results: The median age was 56 years (range 30-77 years) with a male-to-female ratio of 2∶1. Nobody had underlying diseases associated with immunosuppression. Primary extra nodal diseases were observed in 7 cases and only 1 patient had oral involvement. Two patients were in earlystage and 7 in advanced stage by the Ann Arbor stage system. Ki-67 index was 60%-90% in the 9 cases, and 80% or higher in 7 cases. Epstein-Barr virus-encoded RNA expression (EBER) was detected in 4 cases, and 2 of them were positive. Chemotherapy was documented in 9 patients, from which 8 received the cyclophosphamide, doxorubicin, vincristine, prednisone (CHOP)-like regimens as the first-line chemotherapy and responses were observed in 5 (1 complete, 4 partial responses). Three elderly patients were treated with CHOP combined with thalidomide, and 2 of them achieved partial responses. One patient, failed three chemotherapy regimens, accepted thalidomide combined with etopside and achieved stable disease for 10 months. One patient with early stage had disease-free survival of 61.9 months after treatment. The other eight patients experienced recurrence or progression after the first-line chemotherapy, and 6 of them died of disease progression within 2 years after the diagnosis. Conclusion: The HIV-negative PBL patients in this study did not have an apparent association with immunosuppression. Primary extra nodal diseases were common, but only 1 patient had oral involvement. Most patients had advanced stage and poor prognosis. Effectiveness of thalidomide in the treatment of PBL deserves further investigation.

[Plasmablastic lymphoma]

Plasmablastic lymphoma (PBL) is a rare and aggressive subtype of non-Hodgkin lymphoma that commonly occurs in human immunodeficiency virus (HIV)-positive individuals, and affects oral sites. Occasionally, it has been described in HIV-negative patients and involving non-oral sites. Pathologically, PBL is a high-grade B-cell lymphoma that displays the immunophenotype of a terminally differentiated B-lymphocyte with loss of B-cell markers (CD20) and expression of plasma-cell antigens. Epstein-Barr virus infection and MYC rearrangements are frequently observed. Treatment of PBL is challenging because of the lack of established treatment and poor outcomes, with median survival times shorter than one year. In this review, we discuss the clinical and epidemiologic spectrum of PBL as well as its distinct pathological features. Finally, we summarize the currently available approaches for the treatment of patients with PBL.

Ileo-ileal Intussusception and Bowel Obstruction Caused by Plasmablastic Lymphoma of Small Bowel- A Rare Entity in Rare Location

Intussusception of small bowel is considered a rare cause of bowel obstruction in adults accounting for only about 1% of bowel obstruction in adults. Intussusception in adults is uncommon with 95% cases of intussusceptions occurring in children. Adult intussusception from small intestinal lymphoma is also rare with only 36 cases reported in the literature between 2000 and 2011. Plasmablastic lymphoma (PBL) is an aggressive lymphoid neoplasm usually seen in the oral cavity in the clinical setting of human immunodeficiency virus (HIV) infection. Plasmablastic lymphoma of the small intestine is extremely rare. Here, we report a case of plasmablastic lymphoma of small bowel with ileoileal intussusception in an HIV-negative immunocompetent male patient.

EBV-positive diffuse large B-cell lymphoma of the elderly: 2016 update on diagnosis, risk-stratification, and management

Epstein-Barr virus (EBV)-positive diffuse large B-cell lymphoma (DLBCL) of the elderly is a provisional entity included in the 2008 WHO classification of lymphoid neoplasms. It is a disease typically seen in the elderly and thought to be associated with chronic EBV infection and severe immunosuppression with a component of immunosenescence. Recent research, however, has suggested that EBV-positive DLBCL can be seen in younger, immunocompetent patients. The diagnosis of EBV-positive DLBCL of the elderly is made through a careful pathological evaluation. The differential diagnosis includes infectious mononucleosis (specifically in younger patients), lymphomatoid granulomatosis, Hodgkin lymphoma, and gray zone lymphoma, among others. Detection of EBV-encoded RNA (EBER) is considered standard for diagnosis; however, a clear cutoff for positivity has not been defined. The International Prognostic Index (IPI), and the Oyama score can be used for risk-stratification. The Oyama score includes age >70 years and presence of B symptoms. The expression of CD30 is emerging as a potential adverse, and targetable, prognostic factor. Patients with EBV-positive DLBCL should be staged and managed following similar guidelines than patients with EBV-negative DLBCL. It has been suggested, however, that EBV-positive patients have a worse prognosis than EBV-negative counterparts in the era of chemoimmunotherapy. There is an opportunity to study and develop targeted therapy in the management of patients with EBV-positive DLBCL.

Clinical management of HIV-associated hematologic malignancies

HIV is associated with an excess risk for lymphoid malignancies. Although the risk of lymphoma has decreased in HIV-infected individuals in the era of effective combination antiretroviral therapy, it remains high. Treatment outcomes have improved due to improvements in HIV and cancer therapeutics for the common HIV-associated lymphomas. R-CHOP/R-EPOCH are the standard of care for HIV-associated diffuse large B-cell lymphoma. HIV-infected patients with Burkitt lymphoma and good performance status should receive dose-intensive regimens. HIV-infected patients with primary central nervous system lymphoma can respond favorably to high-dose methotrexate-based therapy. In many cases, treatment and expected outcomes for HIV-infected patients with either Hodgkin or non-Hodgkin's lymphomas are very similar to HIV-negative patients. There is currently no standard treatment for HIV-associated multicentric Castleman disease or primary effusion lymphoma. For those hematologic cancers in which transplantation is part of standard care, this modality should be considered an option in those with well-controlled HIV infection.

Plasmablastic Lymphoma Mimicking Acute Pancreatitis

Background. Plasmablastic lymphoma (PBL) is a rare B-cell neoplasm. It predominantly occurs in the oral cavity of human immunodeficiency virus (HIV)-positive patients and exhibits a highly aggressive clinical behavior. Case Presentation. We describe an unusual case of a 37-year-old HIV-positive male who presented with acute pancreatitis secondary to multiple peripancreatic masses compressing the pancreas. Histopathological examination of the lesions showed diffuse and cohesive pattern of large B-cells resembling immunoblasts or plasmablasts. The neoplastic cells were positive for BOB1 and MUM1, partially positive for CD79a, and negative for CD20, CD56, CD138, CD3, CD5, AE1/AE3, and HHV8. Epstein-Barr virus-encoded RNA in situ hybridization was positive. These features were consistent with PBL. The patient was initiated on cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) chemotherapy, demonstrating a striking response. Conclusion. To our research, this is the first report of PBL with the initial presentation of acute pancreatitis. The findings in this case suggest that PBL should be included in the differential diagnosis of pancreatic and peripancreatic tumors.

Long-term remission in a case of plasmablastic lymphoma treated with COMP (cyclophosphamide, liposomal doxorubicin, vincristine, prednisone) and bortezomib

Plasmablastic lymphoma (PBL) is a rare subtype of non-Hodgkin lymphomas (NHL) strongly associated with HIV infection, even if cases in other immunosuppressed patients such as solid organ transplant recipients and in immunocompetent individuals have been increasingly reported. Current treatment strategy for HIV-negative patients is similar to DLBCL as first-line treatment, but durable remissions are seldom observed. Anthracycline-containing regimens could be too toxic for elderly patients and/or with cardiac failure, because a non-pegylated liposomal doxorubicin (NLD) could be used in this field. Bortezomib, a proteasome inhibitor currently approved for patients with multiple myeloma and relapsed mantle-cell lymphoma, has recently showed clinical activity in PBL patients. Herein, we report a rapid and long-term remission of a PBL patient with cardiac failure and that had previously received a double kidney transplant, treated front-line with COMP (with a NLD substituted for doxorubicin) followed by subcutaneous bortezomib consolidation. We suggest first-line treatment outcome is determinant for PBL patients. Bortezomib has a promising role and should be incorporated in future clinical trials and NLD could represent a suitable option for patients with cardiac failure or high cardiovascular risk.

A lymphomagenic role for HIV beyond immune suppression?

Despite the immune reconstitution promoted by combined antiretroviral therapy (cART), lymphomas still represent the most common type of cancer in HIV-infected individuals. Cofactors related to immunodeficiency such as oncogenic viruses, chronic antigenic stimulation, and cytokine overproduction are thought to be the main drivers of HIV lymphomagenesis, although the current scenario does not convincingly explain the still-high incidence of lymphomas and the occurrence of peculiar lymphoma histotypes in HIV-infected patients under cART. Recent findings are challenging the current view of a mainly indirect role of HIV in lymphoma development and support the possibility that HIV may directly contribute to lymphomagenesis. In fact, mechanisms other than immune suppression involve biologic effects mediated by HIV products that are secreted and accumulate in lymphoid tissues, mainly within lymph node germinal centers. Notably, HIV-infected patients with lymphomas, but not those not affected by these tumors, were recently shown to carry HIV p17 protein variants with enhanced B-cell clonogenic activity. HIV p17 protein variants were characterized by the presence of distinct insertions at the C-terminal region of the protein responsible for a structural destabilization and the acquisition of novel biologic properties. These data are changing the current paradigm assuming that HIV is only indirectly related to lymphomagenesis. Furthermore, these recent findings are consistent with a role of HIV as a critical microenvironmental factor promoting lymphoma development and pave the way for further studies that may lead to the design of more effective strategies for an early identification and improved control of lymphomas in the HIV setting.

A striking response of plasmablastic lymphoma of the oral cavity to bortezomib: a case report

Background

Plasmablastic lymphoma (PBL) is a rare and aggressive subtype of non-Hodgkin diffuse large B-cell lymphoma originally with a predilection to the oral cavity of patients infected with HIV. However, PBL of extraoral sites possesses clinicopathological characteristics distinct from oral PBL. Recently, therapeutic approaches using a proteasome inhibitor bortezomib to PBL of extraoral sites have been reported. We present a PBL patient with a bulky tumor of the oral cavity, who dramatically responded to bortezomib.

Case Presentation

The patient was a 58 year-old Japanese male, who presented with a rapidly progressive history of a swelling on his left cheek and restricted mouth opening. He did not have a history or evidence of immunosuppression including HIV infection. A computed tomography demonstrated a bulky tumor in the oral cavity without enlarged lymph nodes. The tumor showed the proliferation of large lymphoid cells with centroblastic morphology, which were positive for CD138, CD38, CD56 and MUM-1, and negative for CD20, CD79a, BCL-6 and HHV8. The Ki-67 proliferation index was almost 100 %. Neither osteolytic lesions nor M-protein was observed. One week after the initiation of bortezomib, a marked regression of the oral tumor was obtained.

Conclusions

Thus, our case demonstrated the effectiveness of bortezomib on PBL of the oral cavity as well as the extraoral sites.

Spontaneous regression of plasmablastic lymphoma in an elderly human immunodeficiency virus (HIV)-negative patient

Plasmablastic lymphoma (PBL) is an aggressive lymphoma commonly associated with human immunodeficiency virus (HIV) infection. Herein we describe a rare case of PBL that spontaneously regressed. An 80-year-old man was referred to our hospital owing to an exophytic gingival tumor in the right maxillary second molar region. He had no significant past medical history, and a screening test for HIV was negative. Imaging showed that the tumor measured 26 × 23 × 16 mm and was confined in the alveolar bone. The tumor was histologically comprised of highly proliferative immunoblastic cells positive for CD138 and Epstein-Barr virus (EBV)-encoded RNA. Monoclonal IgH chain gene rearrangement was detected via polymerase chain reaction. After biopsy and diagnosis of PBL, the tumor began to decrease in size and had apparently disappeared at the time of surgery. There was no histological evidence of a residual lesion in the surgical specimen. In conclusion, a minority of immunosenescence-associated PBLs in the elderly should be recognized as a unique clinicopathological entity distinct from common aggressive PBL.

How I treat posttransplant lymphoproliferative disorders

Posttransplant lymphoproliferative disorder (PTLD) is a potentially fatal disorder arising after solid organ transplant (SOT) or hematopoietic stem cell transplant (HSCT). Iatrogenically impaired immune surveillance and Epstein-Barr virus (EBV) primary infection/reactivation are key factors in the pathogenesis. However, current knowledge on all aspects of PTLD is limited due to its rarity, morphologic heterogeneity, and the lack of prospective trials. Furthermore, the broad spectrum of underlying immune disorders and the type of graft represent important confounding factors. Despite these limitations, several reviews have been written aimed at offering a guide for pathologists and clinicians in diagnosing and treating PTLD. Rather than providing another classical review on PTLD, this "How I Treat" article, based on 2 case reports, focuses on specific challenges, different perspectives, and novel insights regarding the pathogenesis, diagnosis, and treatment of PTLD. These challenges include the wide variety of PTLD presentation (making treatment optimization difficult), the impact of EBV on pathogenesis and clinical behavior, and the controversial treatment of Burkitt lymphoma (BL)-PTLD.

Plasmablastic Lymphoma: A Review of Current Knowledge and Future Directions

Plasmablastic lymphoma (PBL) is an aggressive subtype of non-Hodgkin's lymphoma (NHL), which frequently arises in the oral cavity of human immunodeficiency virus (HIV) infected patients. PBL shows diffuse proliferation of large neoplastic cells resembling B-immunoblasts/plasmablasts, or with plasmacytic features and an immunophenotype of plasma cells. PBL remains a diagnostic challenge due to its peculiar morphology and an immunohistochemical profile similar to plasma cell myeloma (PCM). PBL is also a therapeutic challenge with a clinical course characterized by a high rate of relapse and death. There is no standard chemotherapy protocol for treatment of PBL. Cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) or CHOP-like regimens have been the backbone while more intensive regimens such as cyclophosphamide, vincristine, doxorubicin, high-dose methotrexate/ifosfamide, etoposide, high-dose cytarabine (CODOX-M/IVAC), or dose-adjusted etoposide, prednisone, vincristine, cyclophosphamide, and doxorubicin (DA-EPOCH) are possible options. Recently, a few studies have reported the potential value of the proteasome inhibitor bortezomib and thalidomide in PBL patients. The introduction of genes encoding artificial receptors called chimeric antigen receptors (CARs) and CAR-modified T cells targeted to the B cell-specific CD19 antigen have demonstrated promising results in multiple early clinical trials. The aim of this paper is to review the recent advances in epidemiology; pathophysiology; clinical, pathologic, and molecular characteristics; therapy; and outcome in patients with PBL.